Injection Nozzles
The injection nozzles spray fuel into a prechamber as each compression stroke occurs. Each nozzle has a fuel supply and return line. Nozzles can be disassembled, cleaned and adjusted to correct defective spray patterns. See Fig 1.
Shims are used to correct nozzle opening pressures, and are available in 43 sizes in increments of .001" (.025 mm) from .035-.077" (0.9-1.95 mm). Changing one size nozzle shim will change injection pressure by 50 psi (3.5 kg/cm2 ). Never use more than one shim.